X-joint for surgical instruments



Dec. 13, 1955 L, TABRAH 2,726,657

X-JOINT FOR SURGICAL INSTRUMENTS Filed Feb. 8, 1954 I 2 Sheets-Sheet 1 FRANK L. TABRAH O INVENTOR.

r I 6 ae t q" FIG-.8 88 g Dec. 13, 1955 TABRAH 2,726,657

X-JOINT FOR SURGICAL INSTRUMENTS FIG-3 wwweuvgsggg FRANK L. TABRAH IN VEN TOR.

United States Patent FOR SURGICAL INSTRUMENTS .ErankL. Tabrah,.Bllingham, .Wash.

*Applieation Februar s, 1954, Serial No. 408,633

.2 .Claims. .(Cl..128321) Mydnvention relates to surgical instruments, and more particularly, to :an improved x joint :for surgical .instruments. #Briefly, the :invention includes beveling and soundingtheopposed surfaces forming 'cracks at the .X- 'joint=sothat sutures and lig-aturesiwill :not catch on the yjointzwhen the instrument is in'use.

In surgery, there are-frequent operations-involving" the use of surgical forceps, hemostats, 'ligators, and needle holders wherein a suture or a ligature is looped around the instrument'and slid downthe sameto form a knot, or in whichithetinstrumentaispassedthrough an already .-formedloop, in either direction,.r.elative to thetlongitu- 'dinal axis of the instrument. Considerable trouble'has been caused in the past by the X-joint catching the suture or ligature. This either may be troublesome to free or may actually break the thread. It will be evident that it is desirable to avoid this because of the loss of precious time, or weakening of the suture especially in diificult operations. The X-joint in such tools may be of various types such as a mortise-tenon type or a scarf type; but in each case there are exposed cracks to cause the trouble. The problem is not solved by merely having close tolerances at these joints because in time the instruments inevitably become worn or corroded at the joints due to frequent sterilization and previous attempts at solutions have not provided for snagproofing the instrument when the suture slides along it in either direction relative to its longitudinal axis.

The objects of my invention include: to provide an X-joint in a surgical instrument which will not snag by a shoulder or crevice any thread-like member used in an operation, such as a ligature. When closing an instrument with its X-joint lying flat on gauze Sponges in the operative field the gauze strands sometime inadvertently become caught in the closing shoulders of conventional instruments, preventing further manipulation of the instrument until it is freed and it is an objective of my invention to prevent this trouble. It is a further object to devise such a joint which will be economical to manufacture, which will not snag despite deterioration from wear and corrosion, which will be easier to clean and sterilize and keep rust-free, and which will be operative over the life of the instrument.

My invention will be best understood, together with additional objectives and advantages thereof, from a reading of the following description, read with reference to the drawings, in which:

Figure 1 is a perspective view showing a pair of surgical instruments embodying my invention in the act of tying a ligature;

Figure 2 is an enlarged, perspective view of the X- joint portion of such instrument;

Figure 3 is an enlarged side view of the structure shown in Figure 2;

Figure 4 is a fragmentary side view of a first of the leverage members forming the X-joint;

Figure 5 is a plan view of said first leverage member;

"ice

Figure *6 is -a fragmentary *side view of the' second leveragemember;

Figure is' aflview siniilar*to -Figure fi except taken "on the opposite aside; and

It will be understood that surgical instruments used in forming suturesx and ligaturesmay be 'of'various types, depending -upon "the particular "operation involved, and the applicationof the presentinvention' will be similar in each case. Such. instruments include ligators, forceps,

needle holders, and hemostats and all have )Gjoints,

"formed in some way. In "the drawings, I have shown principally what ma-y be =termed a *mortise-tenon type of X-joint butit will be-apparent that the improvement canbe -applieti to a-scarf type of jointpas shown in Figure 8. =Figure l shows :a'pair of instruments A :and B l in the "operation of tying the suture. -A loop -has been formedin suture "material around :the handle portion -.'of f instrument A in Figure ill; and instrument fB is being used :to :-slide the loop :down the leverage .members r10 .:and 512 :of instrument A .past "the X-joint 14 ltoimake theitie. This .is :typical .of various steps :in imakin gt instrumenttties in surgery in which .there-is. likeli- "hood :of =-a. ligature :or .surface catching in :an X,-joint of conventionalconstruction.

As in most of these instruments, ligator A has a pair of handle rings 20, 22, formed on leverage members 10 and 12. Also, in order to secure the instrument automatically in locked position, adjustable catch means are provided by a multi-toothed ratchet 24 and a pawl 26 on leverage members 12 and 10 respectively. The jaws 30, 32, formed on leverage members 10 and 12 respectively, have rough faces, as at 34, providing positive grips.

X-joint 14 has essentially two components: tenon 40 formed on leverage member .12 adjacent jaw 32 and mortise 42 formed on leverage member 10 adjacent jaw 30. A pivotal connection therebetween is formed by a pin 44 set in leverage member 10 and extending through an opening 46 in tenon 40.

The X-joint forms a series of pairs of opposed, adjacent surfaces on leverage members 10 and 12 which move relative to each other, as for example surfaces 50, 52; 54, 56; 58, 60; and 62, 64. ments these surfaces are parallel in each pair and are either spaced apart far enough when manufactured to catch a thread in the formed crevice or'later separated by wear. During surgical operations, there is opportunity to snag a suture or ligator by catching in such crevice, particularly if a loop is being formed around and slid along the instrument.

My solution to this problem is to bevel and round these surfaces so that they diverge as they extend outwardly, thus forming V-shaped crevices. This beveling may be in a single plane but it is preferable to round the corners, particularly the outer corner, as at and 72 in Figures 2 and 3 respectively. It will be noted in Figure 3 that the angle formed between these surfaces, as 50, 52, is shown as considerably more than a right angle. To avoid such snagging as would hamper sliding a thread or suture along the instrument, the angles shown in the drawings of approximately degrees have been found most workable in easily passing such thread along the instrument. This angle should not be less than approximately 120 degrees. A median plane, bisecting this angle and disposed normal to the central plane in which the leverage members move, includes the apex of the obtuse angle. Each such apex lies at or is located approximately at the joinder of the opposed surfaces forming a bevel and is wholly to one side of said central plane.

In conventional instru- By these means no further problem arises with snagging of sutures, or the catching of unwanted materials between the shoulder surfaces. The joint is made easier to clean and maintain. Manufacture is simplified, since close tolerances are not necessary as in the conventional abutting shoulder surfaces of present X-joint instruments. In the scarf type X-joint, shown in Figure 8, there are likewise a plurality of opposed adjacent surfaces, as 80, 82, on leverage members 86, 84, respectively which move relative each other with the median plane between the opposed surfaces disposed at right angles to the plane in which the leverage members move. These opposed, adjacent surfaces are relieved in the manner above described with a mortise and tenon type joint. In this type of joint rear surface 88 may be considerably raised from the companion surface 90 and of such contour that there is no necessity for beveling these surfaces.

Having thus described my invention, I claim:

1. The improvement in a surgical instrument such as forceps, hemostats, ligators, and needle holders, comprising: said instrument having a pair of leverage members joined together by a mortise and tenon type pivotal X- joint and forming handles on one side of the pivot and forming jaws on the other side of the pivot, said joint forming four pairs of opposed, adjacent surfaces on the two leverage members which move relative to each other forming exposed V-shaped crevices with the median plane between each pair of opposed surfaces being disposed normal to the central plane in which the leverage members move, each pair of said opposed surfaces being beveled and rounded so that they diverge as they'extend outwardly defining an obtuse angle therebetween, the apex of the obtuse angle being located approximately at the joinder of said opposed surfaces, each said crevice including its apex being disposed wholly to one side of the central plane in which the leverage members move.

2. The improvement in a surgical instrument such as forceps, hemostats, ligators, and needle holders, comprising: said instrument having a pair of leverage members joined together by a pivotal X-joint and forming handles on one side of the pivot and forming jaws on the other side of the pivot, said joint forming a plurality of pairs of opposed, adjacent surfaces on the two leverage members which move relative to each other forming exposed V-shaped crevices with the median plane between each pair of opposed surfaces being disposed normal to the central plane in which the leverage members move, each pair of said opposed surfaces being beveled so that they diverge as they extend outwardly definingv an obtuse angle therebetween, the apex of the obtuse angle being located approximately at the joinder of said opposed surfaces, each said crevice including its apex being disposed wholly to one side of the central plane in which the leverage members move.

References Cited in the file of this patent UNITED STATES PATENTS 1,077,086 Lecuyer Oct. 28, 1913 

